KB439409: Adding a new form to an existing attribute and trying to delete it later on via Command Manager, returns the error "Item not found in this collection"

SYMPTOM:
When attempting to remove an Attribute Form from Command Manager, the following error is returned:
"Item not found in this collection"
The executed command is:
REMOVE ATTRIBUTEFORM "SORTING" FROM ATTRIBUTE "Bola" IN FOLDER "\Schema Objects\Attributes\" FROM PROJECT "New Strategy Tutorial";
STEPS TO REPRODUCE:

1. Create a new attribute form for any existing attribute. Make sure that the Form Category is set to “None”.

1. From Command Manager, issue a command for its deletion:

 
REMOVE ATTRIBUTEFORM "TEST" FROM ATTRIBUTE "Customer" IN FOLDER "\Schema Objects\Attributes\Customers\" FROM PROJECT "Strategy Tutorial";
 

1. Observe the error.

Item not found in this collection.
DSSError [Error][0x8004101B]

 
CAUSE:
This is an identified defect that impacts Strategy 9.4.x.
 
ACTION:
A fix has been included in Strategy 10. Please update to this version to take advantage of the fix.
 
WORKAROUND:
The root cause of the issue is related to the Form Category being set to “None”. Changing this to “Date” or any other user defined Category will make the form to be successfully deleted.
 
KB439409